Computing and Manipulation in Design - a Pedagogical Experience Using Symmetry

The concept of symmetry has been usually restricted to bilateral symmetry, though in an extended sense it refers to any isometric transformation that maintains a certain shape invariant. Groups of operations such as translation, rotation, reflection and combinations of these originate patterns classified by modern mathematics as point groups, friezes and wallpapers (March and Steadman, 1974). This extended notion represents a tool for the recognition and reproduction of patterns, a primal aspect of the perception, comprehension and description of everything that we see. Another aspect of this process is the perception of shapes, primary and emergent. Primary shapes are the ones explicitly represented and emergent shapes are the ones implicit in the others (Gero and Yan, 1994). Some groups of shapes known as Semantic Shapes are especially meaningful in architecture, expressing visual features so as symmetry, rhythm, movement and balance. The extended understanding of the concept of symmetry might improve the development of cognitive abilities concerning the creation, recognition and meaning of forms and shapes, aspects of visual reasoning involved in the design process. This paper discusses the development of a pedagogical experience concerned with the application of the concept of symmetry in the creative generation of forms using computational tools and manipulation. The experience has been carried out since 1995 with 3rd year architectural design students. For the exploration of compositions based on symmetry operations with computational support we followed a method developed by Celani (2003) comprising the automatic generation and update of symmetry patterns using AutoCAD. The exercises with computational support were combined with other different exercises in each semester. The first approach combined the creation of two-dimensional patterns to their application and to their modeling into three-dimensions. The second approach combined the work with computational support with work with physical models and mirrors and the analysis of the created patterns. And the third approach combined the computational tasks with work with two-dimensional physical shapes and mirrors. The student’s work was analyzed under aspects such as Discretion/ Continuity –the creation of isolated groups of shapes or continuous overlapped patterns; Generation of Meta-Shapes –the emergence of new shapes from the geometrical relation between the generative shape and the structure of the symmetrical arrangement; Modes of Representation –the visual aspects of the generative shape such as color and shading; Visual Reasoning –the derivation of 3D compositions from 2D patterns by their progressive analysis and recognition; Conscious Interaction –the simultaneous creation and analysis of symmetry compositions, whether with computational support or with physical shapes and mirrors. The combined work with computational support and with physical models and mirrors enhanced the students understanding on the extended concept of symmetry. The conscious creation and analysis of the patterns also stimulated the student’s understanding over the different semantic possibilities involved in the exploration of forms and shapes in two or three dimensions. The method allowed the development of both syntactic and semantic aspects of visual reasoning, enhancing the students’ visual repertoire. This constitutes an important strategy in the building of the cognitive abilities used in the architectural design process